Commit 3cae32b4 authored by Paolo Abeni's avatar Paolo Abeni
Browse files

Merge branch 'separate-smc-parameter-settings-from-tcp-sysctls' 

Wen Gu says:

====================
Separate SMC parameter settings from TCP sysctls

SMC shares some sysctls with TCP, but considering the difference
between these two protocols, it may not be very suitable for SMC
to reuse TCP parameter settings in some cases, such as keepalive
time or buffer size.

So this patch set aims to introduce some SMC specific sysctls to
independently and flexibly set the parameters that suit SMC.
====================

Link: https://lore.kernel.org/r/1663667542-119851-1-git-send-email-guwen@linux.alibaba.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parents 9b17dbd9 0227f058

Documentation/networking/smc-sysctl.rst

+25 −0
Original line number Diff line number Diff line
@@ -34,3 +34,28 @@ smcr_buf_type - INTEGER 
        - 1 - Use virtually contiguous buffers

        - 2 - Mixed use of the two types. Try physically contiguous buffers first.

          If not available, use virtually contiguous buffers then.



smcr_testlink_time - INTEGER

	How frequently SMC-R link sends out TEST_LINK LLC messages to confirm

	viability, after the last activity of connections on it. Value 0 means

	disabling TEST_LINK.



	Default: 30 seconds.



wmem - INTEGER

	Initial size of send buffer used by SMC sockets.

	The default value inherits from net.ipv4.tcp_wmem[1].



	The minimum value is 16KiB and there is no hard limit for max value, but

	only allowed 512KiB for SMC-R and 1MiB for SMC-D.



	Default: 16K



rmem - INTEGER

	Initial size of receive buffer (RMB) used by SMC sockets.

	The default value inherits from net.ipv4.tcp_rmem[1].



	The minimum value is 16KiB and there is no hard limit for max value, but

	only allowed 512KiB for SMC-R and 1MiB for SMC-D.



	Default: 128K

include/net/netns/smc.h

+3 −0
Original line number Diff line number Diff line
@@ -19,5 +19,8 @@ struct netns_smc { 
#endif

	unsigned int			sysctl_autocorking_size;

	unsigned int			sysctl_smcr_buf_type;

	int				sysctl_smcr_testlink_time;

	int				sysctl_wmem;

	int				sysctl_rmem;

};

#endif

net/smc/af_smc.c

+2 −3
Original line number Diff line number Diff line
@@ -379,6 +379,8 @@ static struct sock *smc_sock_alloc(struct net *net, struct socket *sock, 
	sk->sk_state = SMC_INIT;

	sk->sk_destruct = smc_destruct;

	sk->sk_protocol = protocol;

	WRITE_ONCE(sk->sk_sndbuf, READ_ONCE(net->smc.sysctl_wmem));

	WRITE_ONCE(sk->sk_rcvbuf, READ_ONCE(net->smc.sysctl_rmem));

	smc = smc_sk(sk);

	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);

	INIT_WORK(&smc->connect_work, smc_connect_work);
@@ -3253,9 +3255,6 @@ static int __smc_create(struct net *net, struct socket *sock, int protocol, 
		smc->clcsock = clcsock;

	}



	smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);

	smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);



out:

	return rc;

}

net/smc/smc_core.c

+4 −4
Original line number Diff line number Diff line
@@ -2307,10 +2307,10 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) 


	if (is_rmb)

		/* use socket recv buffer size (w/o overhead) as start value */

		sk_buf_size = smc->sk.sk_rcvbuf / 2;

		sk_buf_size = smc->sk.sk_rcvbuf;

	else

		/* use socket send buffer size (w/o overhead) as start value */

		sk_buf_size = smc->sk.sk_sndbuf / 2;

		sk_buf_size = smc->sk.sk_sndbuf;



	for (bufsize_short = smc_compress_bufsize(sk_buf_size, is_smcd, is_rmb);

	     bufsize_short >= 0; bufsize_short--) {
@@ -2369,7 +2369,7 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) 
	if (is_rmb) {

		conn->rmb_desc = buf_desc;

		conn->rmbe_size_short = bufsize_short;

		smc->sk.sk_rcvbuf = bufsize * 2;

		smc->sk.sk_rcvbuf = bufsize;

		atomic_set(&conn->bytes_to_rcv, 0);

		conn->rmbe_update_limit =

			smc_rmb_wnd_update_limit(buf_desc->len);
@@ -2377,7 +2377,7 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) 
			smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */

	} else {

		conn->sndbuf_desc = buf_desc;

		smc->sk.sk_sndbuf = bufsize * 2;

		smc->sk.sk_sndbuf = bufsize;

		atomic_set(&conn->sndbuf_space, bufsize);

	}

	return 0;

net/smc/smc_llc.c

+1 −1
Original line number Diff line number Diff line
@@ -2127,7 +2127,7 @@ void smc_llc_lgr_init(struct smc_link_group *lgr, struct smc_sock *smc) 
	init_waitqueue_head(&lgr->llc_flow_waiter);

	init_waitqueue_head(&lgr->llc_msg_waiter);

	mutex_init(&lgr->llc_conf_mutex);

	lgr->llc_testlink_time = READ_ONCE(net->ipv4.sysctl_tcp_keepalive_time);

	lgr->llc_testlink_time = READ_ONCE(net->smc.sysctl_smcr_testlink_time);

}



/* called after lgr was removed from lgr_list */